imx: mx6sx: move MX6SX to Kconfig entry

If including MX6SX in CONFIG_SYS_EXTRA_OPTIONS, CONFIG_ROM_UNIFIED_SECTIONS
will not effect.So move MX6SX to Kconfig entry from CONFIG_SYS_EXTRA_OPTIONS to
"select MX6SX" to boards using i.MX6 SoloX.

Signed-off-by: Peng Fan <van.freenix@gmail.com>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>

arch/arm/cpu/armv7/mx6/Kconfig

@@ -104,12 +104,14 @@ config TARGET_MX6SLEVK
 
 config TARGET_MX6SXSABRESD
 	bool "mx6sxsabresd"
+	select MX6SX
 	select SUPPORT_SPL
 	select DM
 	select DM_THERMAL
 
 config TARGET_MX6SXSABREAUTO
         bool "mx6sxsabreauto"
+	select MX6SX
         select DM
         select DM_THERMAL
 

configs/mx6sxsabreauto_defconfig

@@ -1,7 +1,7 @@
 CONFIG_ARM=y
 CONFIG_ARCH_MX6=y
 CONFIG_TARGET_MX6SXSABREAUTO=y
-CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=board/freescale/mx6sxsabreauto/imximage.cfg,MX6SX"
+CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=board/freescale/mx6sxsabreauto/imximage.cfg"
 # CONFIG_CMD_IMLS is not set
 # CONFIG_CMD_FLASH is not set
 CONFIG_CMD_GPIO=y

configs/mx6sxsabresd_defconfig

@@ -1,7 +1,7 @@
 CONFIG_ARM=y
 CONFIG_ARCH_MX6=y
 CONFIG_TARGET_MX6SXSABRESD=y
-CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=board/freescale/mx6sxsabresd/imximage.cfg,MX6SX"
+CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=board/freescale/mx6sxsabresd/imximage.cfg"
 # CONFIG_CMD_IMLS is not set
 # CONFIG_CMD_FLASH is not set
 CONFIG_CMD_GPIO=y

configs/mx6sxsabresd_spl_defconfig

@@ -2,7 +2,7 @@ CONFIG_ARM=y
 CONFIG_ARCH_MX6=y
 CONFIG_TARGET_MX6SXSABRESD=y
 CONFIG_SPL=y
-CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=arch/arm/imx-common/spl_sd.cfg,MX6SX"
+CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=arch/arm/imx-common/spl_sd.cfg"
 # CONFIG_CMD_IMLS is not set
 # CONFIG_CMD_FLASH is not set
 CONFIG_CMD_GPIO=y